Modern bandages or wound dressings commonly are combinations of materials incorporating a suitable adhesive for the surrounding skin with a wound pad of absorbent material. The properties of the absorbent material vary with respect to the type of injury. Conventional wound dressings readily absorb fluids and can become saturated with exudate seeping from an open wound, necessitating frequent bandage or dressing changes. Frequent changes can cause wound irritation and discomfort to the patient. Thus, it is important for the wound pad to have minimal adherence to the healing wound.
Proteinaceous exudation from many types of skin lesions is normal during the healing process. Wounds which produce exudate include Stage II and Stage III ulcers, second and third degree burns, skin grafts and donor sites, deep derm abrasions, and lacerations. It is known that proteinaceous exudate acts as an adhesive or glue upon drying to adhere the dressing to the wound. In addition, there is a secondary mechanism of adherence in which new tissue grows into the structure of the wound dressing.
Generally, adherence of the proteinaceous exudate to the dressing is a function of the surface polarity of the material of the wound dressing in direct contact with the wound. Materials having a highly hydroxyl-rich surface, such as cotton gauze, adhere strongly while materials having substantially non-polar surfaces, such as nylon and silicones, do not. However, non-polar materials are less absorbent and trap exudates at the wound surface to retard the healing process.
Thus, there remains a need for a wound dressing which has the capability of absorbing proteinaceous exudate as it appears at the surface of an open wound and yet avoid adherence of the wound dressing to the wound. Accordingly, it is to solving this and other needs that the present invention is directed.